1DSDOT(1)                         BLAS routine                         DSDOT(1)
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NAME

6       DSDOT - accumulation and result
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SYNOPSIS

9       DOUBLE PRECISION FUNCTION DSDOT(N,SX,INCX,SY,INCY)
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11           INTEGER      INCX,INCY,N
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13           REAL         SX(*),SY(*)
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PURPOSE

16       precision accumulation and result.
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18       Returns  D.P. dot product accumulated in D.P., for S.P. SX and SY DSDOT
19       = sum for I = 0 to N-1 of  SX(LX+I*INCX) * SY(LY+I*INCY), where LX =  1
20       if  INCX .GE. 0, else LX = 1+(1-N)*INCX, and LY is defined in a similar
21       way using INCY.
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ARGUMENTS

25       N      (input) INTEGER
26              number of elements in input vector(s)
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28       SX     (input) REAL array, dimension(N)
29              single precision vector with N elements
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31       INCX   (input) INTEGER
32              storage spacing between elements of SX
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34       SY     (input) REAL array, dimension(N)
35              single precision vector with N elements
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37       INCY   (input) INTEGER
38              storage spacing between elements of SY
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40       DSDOT  (output) DOUBLE PRECISION
41              DSDOT  double precision dot product (zero if N.LE.0)
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FURTHER DETAILS

44       REFERENCES
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46       C. L. Lawson, R. J. Hanson, D. R. Kincaid and F. T.
47       Krogh, Basic linear algebra subprograms for Fortran
48       usage, Algorithm No. 539, Transactions on Mathematical
49       Software 5, 3 (September 1979), pp. 308-323.
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51       REVISION HISTORY  (YYMMDD)
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53       791001  DATE WRITTEN
54       890831  Modified array declarations.  (WRB)
55       890831  REVISION DATE from Version 3.2
56       891214  Prologue converted to Version 4.0 format.  (BAB)
57       920310  Corrected  definition  of  LX  in  DESCRIPTION.   (WRB)  920501
58       Reformatted the REFERENCES section.  (WRB)
59       070118  Reformat to LAPACK style (JL)
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64BLAS routine                     November 2008                        DSDOT(1)
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